1. Field of Invention
This invention relates to automatic machines and processes for filling batteries with acid.
2. Prior Art
In the prior art, it is known to assemble automotive batteries completely with the plates and separators assembled in cells and the lids of the batteries sealed to the cases of the batteries. The covers of the batteries have holes for venting gases from the batteries as well as for pouring acid into the batteries in order to cover the plates. The assembled batteries are passed under acid filling machines in order to fill them with acid before the vent caps are placed over the vent/acid fill holes.
In the prior art, it was known to place two concentric tubes into each battery vent. This thereby reduced the fill diameter to the point where the actual filling of the battery was quite slow.
Another method was to have a two-station operation wherein at one station acid would enter the battery by gravity and at the second station excess acid would be sucked out until the acid was at a proper level. In such a method, it was common to have battery acid overflows; with their attendant ecological problems.
Further, in the past, a vacuum system would implode the end cells of the battery which would result in a lower acid level on the end cells of the battery.
It is the desire of the present invention to eliminate the prior art problems regarding filling batteries.
Our battery acid filler apparatus comprises a supply pump means for supplying acid under a first head to a battery; said battery having a plurality of filler ports; connecting tube means are provided comprising a plurality of tubes each connected at one end with said supply pump means and in fluid flow communication therewith for receiving acid therefrom; level pump means are provided comprising a plurality of level pumps in fluid flow communication from each of their discharge ends to the other ends of each connecting tube; said level pump means being capable of producing a second head higher than said first head produced by supply pump means; filler head means are provided comprising a plurality of filler head tubes each connected to the other end of a different level pump and in fluid flow communication therewith; each of these filler head tubes terminates in a filler spout at the end remote from the end connected to the level pump; each of said filler spouts being dimensioned to fit inside a filler port, with a slight clearance therebetween to allow for passage of air; sequencing means are connected to said filler head means to move said filler spouts into said filler ports and thereafter to retract said spouts from said ports; said sequencing means controls the flow of acid into said battery in accordance with a preset time interval, such that the battery will be over filled to the point where the acid will rise into the filler port, but not over the top of the port; and once the time interval runs out, the sequencing means turns the level pump means xe2x80x9conxe2x80x9d so that acid is extracted from the filler ports down to the terminal ends of the filler spouts.
The sequencing means controls the supply pump means and the level pump means such that the level pumps are turned xe2x80x9conxe2x80x9d before the supply pump means is turned xe2x80x9conxe2x80x9d. Once the filler spouts are inserted into the filler ports, the level pumps are turned xe2x80x9coffxe2x80x9d thereby permitting acid to flow into the battery from the supply means.
In accordance with the method of our invention, filling a battery with acid comprises the steps of: introducing acid into the filler ports of the battery at a first predetermined pressure for a predetermined time interval to the point where the acid rises into the ports, but not over the top of the ports; and then extracting acid from the ports down to a predetermined level.
Thus we use a pump to act as a valve to stop liquid flow. This is accomplished by having the pressure of the pump higher than the liquid supply pressure.
Further, the pump is used to level an overfilled container. This is accomplished, in part, by inserting the conduit to the intake of the pump into the container to the desired level. Multiple pumps can be used to level multiple cells of a battery, simultaneously.